Magnetic reversals have to support
a. the theory of pangaea.
c. sea-floor spreading.
b. the age of the earth.
d. the theory of gondwana.

Correct answer choice is :

C) Sea-floor spreading.

Explanation:

The Earth's magnetic field is believed to be produced by fluid changes in the liquid, outer part of the Earth's core, which is mainly formed of iron. The reversal method is not completely intermittent as it is on the sun, whose fascinating field changes every 11 years. The geologic record shows that numbers of pole cancellations have happened during Earth's history, they happen when pieces of iron atoms in Earth's liquid outer core become reverse-aligned, like tiny electromagnets located in the different direction from those around them.

the higher the current the higher the mag field around it the higher the influence on the compass

the answer is ampere

the ampere is used to measure electricity. an ampere is a unit of electric current equal. a unit of measure for the flow of current in a circuit. one ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance.